New Study Shows Vegan Diet Effective Treatment for Type 2 Diabetes
A new study appearing in the August issue of Diabetes Care shows that a low-fat vegan diet treats type 2 diabetes more effectively than a standard diabetes diet and may be more effective than single-agent therapy with oral diabetes drugs. The randomized controlled trial was conducted by doctors and dietitians with PCRM, the George Washington University, and the University of Toronto, with funding from the National Institutes of Health and the Diabetes Action Research and Education Foundation.
PCRM president Neal Barnard, M.D., the study’s lead researcher, joined Joshua Cohen, M.D., of the George Washington University Medical Center, and David Jenkins, M.D., Ph.D., Sc.D., of the University of Toronto for a news briefing in Washington on July 27 to release the details of the study. Two study participants also discussed the dramatic health improvements they experienced on the vegan intervention diet.
The study involved 99 individuals with type 2 diabetes. Half the group was assigned to follow a low-fat vegan diet for 22 weeks, and the other half was asked to follow a diet based on the American Diabetes Association's guidelines. While both groups experienced significant reductions in hemoglobin A1c (a measure of blood sugar levels over a prolonged period), weight, plasma lipid concentration, and urinary albumin excretion, medication-stable participants in the vegan group experienced significantly greater reductions in A1c, weight, body mass index, waist circumference, total cholesterol, and LDL cholesterol.
“The new diet approach does not rely on any limits on carbohydrates, calories, or portion sizes, and appears to be more effective than typical ‘diabetes diets’,” Dr. Barnard said. “And all the ‘side effects’ were good ones—weight loss, lower cholesterol, and overall better health.
Vance Warren, a 36-year-old study participant and former Washington, D.C., police officer, discussed how changing his diet changed his life. When he was first diagnosed with diabetes at the age of 31, he did not take it seriously, he said at the press conference. Then he began developing problems with his eyesight and renal function. He tried several different diets, but none of them worked. However, since he began the intervention diet in January 2005, his A1c dropped from over 9 percent to 5.3 percent (normal values are below 6.0 percent), his cholesterol dropped from 221 to 148 points, and he has lost 74 pounds.
Virginia resident Nancy Boughn had a similar experience with health improvements on the intervention diet. The diet was “a really simple change,” she said. “I’d spent eight and a half years measuring,” she added, referring to the portion control that is typical of most diabetes diets. Boughn’s A1c dropped from 8.3 to 6.4 percent, and she had to discontinue one of her medications even before the end of the 22-week study.
Dr. Jenkins concluded that doctors need to put a much greater emphasis on diet for diabetes treatment. Dr. Cohen also noted that, "despite the fact that the vegan diet places no limits on carbohydrates or calories, it is at least as good, if not better than traditional approaches."